具滾根槽之刮齒刀應力分析與其創生用之滾齒刀設計

Stress Analysis of Shaving Cutter with Relief Portion and Design of the Generating Hob Cutter

蔡鋒穎(Feng-Ying Tsai)

國立虎尾科技大學/工程學院/動力機械工程研究所/碩士(2006年)

摘要

論文主要是針對應用於刮齒刀根槽製造的瘤頭滾齒刀設計及其創生之刮齒刀進行研究。由於滾齒刀設計參數眾多，如何選定合適的參數是刀具設計的重要基礎。本研究利用座標轉換、齒輪嚙合原理及微分方程理論推導出滾齒刀所加工出的刮齒刀根槽外形，並利用兩種不同之最佳化設計方法，來求得符合目標函數、喉頭寬度限制、過切量限制之最佳化參數設計值，讓設計者能快速取得滾齒刀之最佳化設計參數，並藉由CATIA繪圖軟體建構出刮齒刀實體模型。
為了解應用本研究所生產之刮齒刀特性，本文亦針對最佳化程式獲得之參數所建構出的刀具實體，進行有限元素分析，透過不同之元素類型及負載設定，模擬刀具實際加工情形，並觀察其齒面接觸應力分佈情形。由於在實際的刮齒過程中，刮齒刀具有插槽刃口且為多齒接觸，而切削應力與刃口接觸位置有極大的影響，因此本文計算出齒面間的接觸橢圓，作為刮齒刀三維應力分析時之受力條件之依據。最後透過ANSYS軟體，來進行具插槽之刮齒刀的強度分析，所得到的應力分佈情形可以用來與傳統刮齒刀進行比較，可提供往後較佳的齒形設計參考及改善中凹齒形的依據。

並列摘要

The main objectives in this thesis are studying the design of protuberance hob cutter and the generated shaving cutter. The protuberance hob cutter proposed is used to manufacture the relief portion of the shaving cutter. In the design of hob cutter, the choose of parameters is the most difficult process in the design. Here, the principle of coordinate transformation, the theory of differential geometry, and the theory of gearing are used to determine the complete profile of the shaving cutter. Two different methods of optimun, i.e., global search method and optimum subroutine in Matlab software, are applied to determine the optimum parameters of the hob cutter satisfying the objective function, geometry constraint of throat width, and the constraint of serration depth. The CATIA software is then used to construct the solid modeling of the shaving cutter.
By applying the mathematical model of the shaving cutter derived, the solid modeling is then transformed into the FEM model for the 3-D stress analysis with different load and element type. The contact surface topology method is also used to determine the shaved contact pattern. The stress analysis is then proceeded. This information for the stress analysis can help us to modify the design of shaving cutter and offer better design information for correcting the concave phenomenon in the tooth profile.

參考文獻

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